A Runner’s Journey Through Injury: Resolving Acute Posterior Tibial Tendonitis with COMPEX.

Tendonitis is one of the most frustrating, lingering diagnoses an endurance athlete can face. When I first launched our collaboration with Eliška Klepková—the competitive track athlete and official STRYD Ambassador for Slovakia—she was dealing with a severe, acute case of lower leg tendonitis. As an EMS and recovery specialist, I didn't hesitate for a second. I immediately shipped a COMPEX device to her training camp to accelerate her clinical rehabilitation.

Below, Eliška shares her first-hand case study and the exact protocol she used to rebuild her tissue integrity and return to peak training.

The Reality of Deep Calf and Shin Pain 

At the end of March, I began experiencing debilitating pain along my left calf and deep inner shin. Initially, I brushed it off as a minor case of shin splints—a classic runner's ailment. I slightly decreased my weekly mileage and hoped the discomfort would fade. Instead, the pathology worsened to the point where I completely lost the ability to push off from my left foot during a stride.

Due to localized bruising and severe tenderness, doctors at the hospital initially suspected a tibial stress fracture. While an X-ray ruled out bone fractures, the clinical diagnosis was clear: Posterior Tibial Tendonitis (m. tibialis posterior). This deep muscle of the posterior lower leg plays a massive biomechanical role; it is the primary dynamic stabilizer of the medial longitudinal arch of the foot and assists in plantarflexion (rising onto your tiptoes).

Managing the Acute Phase: Moving Past Outdated Protocols 

The physician's instructions were strict: complete rest, or risk facing a chronic condition lasting six months or more. To optimize my recovery and protect my career, I designed a proactive rehabilitation routine. Every morning, I performed gentle, low-load mobility stretches just to relieve the severe overnight tightness so I could walk across the room. To accelerate the reabsorption of the deep hematoma, I applied targeted topical treatments three times a day.

It is worth noting an important shift in modern sports medicine regarding tendon management: many people still believe that icing an inflamed tendon is the best approach. However, applying ice actually delays long-term tissue regeneration. Cold temperatures cause vasoconstriction, which slows down the body's natural inflammatory response—a vital physiological cascade required to clear cellular debris and deliver repair proteins. Instead of ice, I utilized dry heat to promote baseline localized circulation.

How the COMPEX SP Series Accelerated the Healing Cascade 

The definitive game-changer in my recovery was the introduction of neuromuscular electrical stimulation (NMES) via the Compex SP 2.0. To deactivate the protective muscle guarding and severe hypertonicity of the deep calf complex, I deployed the Muscle Relaxation / Overwork program.

I positioned the electrodes precisely over the anatomical origin and insertion points of the posterior tibialis muscle. I scaled the intensity to elicit strong, visible muscle twitches without crossing into the pain threshold. The immediate physiological feedback was incredible:

• Immediate De-activation: After the very first session, the deep, restrictive muscle tightness was significantly reduced.

• Rapid Timetable to Return: Within just 2 to 3 weeks of strict running cessation combined with daily Compex therapy, I was completely waking up pain-free.

• Safe Progression: I transitioned from active rest to long walks, which smoothly evolved back into short, structured runs.

Today, I am systematically ramping up my training volume and intensity. Most importantly, the Compex device has transitioned from a rehabilitation tool to a mandatory preventative asset. After every single hard run, I hook up the modules to flush out metabolic waste, maintain optimal tissue elasticity, and ensure this injury never returns.

Author: Eliška Klepková

Competitive Athlete, STRYD Slovakia Ambasador & Physical Therapy Specialist